Industrial and Commercial Bank of China Ltd, the world's largest bank by asset, said it will play the pillar role of a major bank and further increase credit support to the real economy, according to a filing to the Shanghai Stock Exchange on Sunday.

Agricultural Bank of China, Bank of China and Postal Savings Bank of China said they reached fast credit growth in the first three quarters this year and will continue to contribute financial strength needed for the stable and high-quality operation of the economy.

China Construction Bank Corp (601939.SS)and Bank of Communications also noted fast credit growth and said they will further step up credit risk management to better serve the economy.

Their pledges of support came after Xi opened the once-in-five-year party Congress in Beijing with a speech on Sunday morning in which he said China would aim for high-quality economic growth and will unwaveringly support the private economy.

The world's second-largest economy narrowly avoided contracting in the second quarter, weighed by widespread COVID-19 lockdowns and the slumping property sector.

During the third quarter, banks ramped up credit support to property industry, infrastructure sector and small- and midsized businesses.

China's big state-owned banks are usually the quickest to respond to the government's policy directions. The banks have warned they are set to face a squeeze on profit margins in the second half as they respond to Beijing's call to boost lending to the real economy.

In September, China Construction Bank announced it plans to set up a 30 billion yuan ($4 billion) fund to finance rental housing to aid the struggling property sector.

(Reporting by Ziyi Tang and Ryan Woo; Editing by Simon Cameron-Moore)